Method of treating a smoking composition to reduce undesirable products therefrom



June 30, 1970 I. MICHELSON 3,517,572

METHOD OF TREATING A SMOKING COMPOSITION TO REDUCE UNDESIRABLE PRODUCTSTHEREFROM Filed Aug. 9, 1968 MMO/V/UM //v 72:20:00

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United [States Patent Ofiice 3,517,672 Patented June 30, 1970 3,517,672METHOD OF TREATING A SMOKING COMPOSI- TION TO REDUCE UNDESIRABLEPRODUCTS THEREFROM Irving Michelson, New Rochelle, N.Y., assignor toAmerican Safety Equipment Corporation, New York, N .Y., a corporation ofNew York Confinuation-in-part of application Ser. No. 67 8,184, Oct, 26,1967. This application Aug. 9, 1968, Ser. No. 751,413

Int. Cl. A24!) 15/02; A24d 1/02 US. Cl. 131-440 5 Claims ABSTRACT OF THEDISCLOSURE A method of treating a smoking composition composed of curedtobacco wrapped in paper is disclosed, said composition containing from0.1% to 1.0%, by weight, of ammonium sulfamate, at least 50% of theammonium ion of the ammonium sulfamate being in the tobacco and at least70% of the sulfamate ion of the ammnoium sulfamate being in the paper,whereby the smoke produced from said tobacco composition has asignificantly reduced amount of components which cause tumors on theskin of mice and other biological damage, and the toxicity of tarscapable of being condensed from said smoke is significantly reducedwhile, at the same time, the taste of said smoke, the burning of saidtobacco composition, and the appearance of the ash resulting from theburning of said composition is not adversely affected. The method forproducing such a composition includes adding ammonium sulfamate to thepaper and allowing the ammonium sulfamate to remain on the paper until asignificant amount of the ammonium ion has migrated to the tobacco.Preferably, the ammonium sulfamate is added to the paper in the form ofa solution (e.g. an aqueous solution).

RELATED APPLICATIONS This application is a continuation-in-part of mycopending application Ser. No. 678,184, filed Oct. 26, 1967.

BACKGROUND OF THE INVENTION In recent years, the concern for the healthof tobacco smokers, particularly cigarette smokers, has increased. Thereason for this concern is because of the evidence gathered byscientists around the world that smoking definitely endangers the healthof the smoker to a greater or lesser extent, depending upon the amountof the smoke, the extent to which it is inhaled, and the personssusceptibility to being injured by tobacco smoke. For example, it isdefinitely established that cigarette smokers are more apt to developlung cancer, bronchitis, emphysema, and suffer other biological damagethan nonsmokers. Figures from Smoking and Health, report of the AdvisoryCommittee to the Surgeon General, indicate that heavy smokers arefifteen to twenty-five times more susceptible to the risk of lung cancerthan that of nonsmokers and that light smokers chances of developinglung cancer is five to ten times that of non-smokers. In addition, themortality of smokers because of bronchitis and emphysema is five toeight times that of non-smokers.

Because of the foregoing and other evidence that smoking is detrimentalto the health and well-being of people of all ages, the federalgovernment of the United States has required all cigarette manufacturersto place on cigarette packages the warning that Cigarette Smoking May BeHazardous to Your Health. In spite of this warning, the consumption ofcigarettes and other tobacco has actually increased from the prioryears. It is thus very apparent that people who are addicted tocigarette smoking are very unlikely to quit merely because they run therisk of having their health seriously impaired.

It is thus a desideratum in the art to produce a tobacco composition,the smoke of which has a reduced amount of components which are apt tocause biological damage to the smoker. It is therefore not surprisingthat in the past decade the prior art has endeavored to produce a safetobacco, particularly safe cigarettes. For the most part, the prior artattempts have centered around the idea of filtering out or screening thetars produced during the smoking of the tobacco. However, this has notbeen entirely satisfactory because inter alia it appears that thematerials produced in the smoking of the cigarette which causebiological damage cannot be filtered out selectively and therefore thefiltered smoke still contains substantially the same proportions ofdeleterious material as the unfiltered smoke.

There have also been attempts to produce safer tobacco for smoking byadding various components which reduce the amount of certain compoundscontained in tobacco smoke which are believed to be carcinogens. Forexample, see Alvord et al., the British Journal of Cancer, 1956, vol. X,pages 498 through 503, and Bentley et al., Analyst, October 1960, vol.85, pages 727 through 730. In addition, attempts have been made toimprove the safety of cigarettes by adding a material to the cigarettepaper which is said to reduce the amount of 3,4-benzopyrene contained inthe smoke produced by the cigarette paper. See US. Pat. 2,859,753. 5Both of the articles referred to above report that the addition of acertain amount of ammonium sulfamate to tobacco reduces the amount of3,4-benzopyrene in the tar recovered from the smoke. The articlesdisagree as to the precise reduction in the content of 3,4-benzopyrenein the tar of the smoke. Whether reducing the amount of this compounddoes in fact render the cigarette smoke safer is open to question.Nevertheless, whether cigarettes are safer because of a reducedbenzopyrene content or not, the fact remains that the addition of about2% or more of ammonium sulfamate to tobacco adversely affects thevarious properties of the tobacco which make it desirable for smoking.For example, ammonium sulfamate is a well-known flameproofing agent fortextiles and paper.

SUMMARY OF THE INVENTION The present invention is based upon thesurprising discovery that ammonium sulfamate added in a certain criticalmanner to smoking compositions composed of cured tobacco wrapped inpaper significantly and materially reduces the amount of components intobacco smoke which cause tumors on the skin of mice but does not alteror affect the taste of the tobacco smoke, the burning properties of thetobacco and paper or the appearance of the ash of said tobacco andpaper. Moreover, the addition of ammonium sulfamate to smokingcompositions in a manner which will be described hereinafter, reducesthe amount of components in smoke produced from such compositions whichhave an adverse effect on the pulmonary functions in test animals(guinea pigs) and damage sebaceous glands in mice.

The above advantages obtained by the compositions produced by the methodof this invention are the result of adding ammonium sulfamate to tobaccocompositions in a certain critical manner. In order to achieve theforegoing results, the ammonium sulfamate is applied to a smokingcomposition composed of tobacco wrapped in paper by contacting the paperwith said ammonium sulfamate. Surprisingly, immediately after theammonium sulfamate is applied, the smoke produced from such acomposition has about the same properties as smoke produced from asmoking composition not containing ammonium sulfamate. However, within aperiod of one to two weeks, I have discovered that the ammonium ion ofthe ammonium sulfamate starts to migrate into the tobacco and after aperiod of about six weeks, about 80% of the ammonium ion has migratedinto the tobacco While the majority of the sulfamate ion has remained onthe paper. It is only after a significant amount of the ammonium ion hasmigrated into the tobacco that the smoke produced from such tobaccoshows a reduction in components which cause tumors in mice and otherbiological damage.

I have also discovered, based on tests conducted heretofore, that whenthe ammonium sulfamate is added directly to tobacco that the reductionin the amount of components causing tumors in mice is not as great aswhen the ammonium sulfamate is added in accordance with the presentinvention.

It is thus an object of the present invention to disclose and provide asmoking composition composed of tobacco wrapped in paper, the smoke ofwhich has a significantly reduced amount of components which causetumors on the skin of mice and harm sebaceous glands on the skin ofmice.

Another object of the present invention is to disclose and embody atreated cigarette which, when smoldered, produces a smoke which hassubstantially the same taste as the smoke produced by a correspondinguntreated cigarette.

It is still a further object of the invention to produce a safercigarette wherein the tobacco of said cigarette contains a significantamount of ammonium ion which is derived from ammonium sulfamate whichhas been applied to the paper of said cigarette.

Still another object of the invention is to disclose and provide a novelmethod for producing the said tobacco compositions and treatedcigarettes, said method allowing for the production of a smokingcomposition and a cigarette wherein the tobacco contains over 50% of theammonium ion derived from ammonium sulfamate which has been added to thepaper, said smoking compositions and cigarettes producing lesscomponents which cause tumors on the skin of mice as well as reducingthe toxicity of tars capable of being condensed from the smoke producedfrom such smoking compositions and cigarettes.

Still another and further object is to provide a novel method forproducing novel tobacco compositions and cigarettes by applying asolution of ammonium sulfamate to the paper of such tobacco compositionsand cigarettes by contacting the paper with a solution containingammonium sulfamate and allowing the thus obtained paper to contact thetobacco for a sufiicient length of time to allow at least 50% of theammonium ion from such ammonium sulfamate to migrate to said tobacco.

BRIEF DESCRIPTION OF THE DRAWING The drawing is a graph showing themigration of ammonium ion from the paper to the tobacco.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The smoking compositionsproduced by the method of this invention are produced by adding acertain critical amount of ammonium sulfamate to said compositions in acertain critical manner. The amount of ammonium sulfamate necessary toproduce the desirable properties possessed by my tobacco composition isbetween about 0.1% and 1.0% based on the total amount of tobacco andcigarette paper which comprise my tobacco compositions. Based uponpresent tests, the presently preferred range of ammonium sulfamate is0.2% to 0.8% by weight and most preferably, from about 0.2% to 0.5% byweight.

The manner in which the ammonium sulfamate is added to the tobaccocompositions produced by the method of this invention is, as notedsupra, critical. The ammonium sulfamate is added to the paper and theammonium sulfamate is allowed to remain on the paper in contact with thetobacco until at least about of the ammonium ion of the ammoniumsulfamate is allowed to migrate to the tobacco. This takes place in aperiod of from two to three weeks, but it is preferred to wait a longerperiod of time, e.g. six weeks, at which time from to of the ammoniumion is present in the tobacco and only 30% to 20% is present in thepaper. At the same time that this is occurring, the majority of thesulfamate ion of the ammonium sulfamate remains on the paper. Preciselywhy this phenomenon occurs is not, at present, completely understood;however, it is clear from biological tests that this migration mustoccur in order to produce safer smoking compositions. Moreover, thesmoking compositions produced by such a method, i.e. migration of theammonium ion into the tobacco, produces smoke which is less toxic thansmoke in which the ammonium sulfamate is added directly to the tobacco.Here again, precisely why this occurs is, at present, not completelyunderstood.

I have determined that a very convenient way in which to add theammonium sulfamate to the paper is via an aqueous solution. The preciseamount of ammonium sulfamate in the solution is not critical providedthat from 0.1% to 1.0% of ammonium sulfamate, based on the total weightof tobacco and paper, is added to the paper. Certain practicalconsiderations however enter into the picture, e.g. the amount of wateradded to the paper should not be so great as to require special removalsteps. Based on experiments, I have determined that a 5% to 50% solutionof ammonium sulfamate is convenient and, most preferably, a 5% to 15%solution. When a solution of this concentration is utilized, the amountof ammonium sulfamate present in the cigarette paper and tobacco iswithin the ranges referred to above.

The ammonium sulfamate solution can be added in any convenient manner,e.g. spraying the solution on the cigarette paper. Because of certainpractical considerations in producing a limited amount of cigarettes fortesting (about 2 million) in the exemplary embodiment the ammoniumsulfamate is added by passing a cigarette through a cylinder of suitablesize and diameter which is filled with a sorbent material such as asponge, the cylinder having an aperture or bore which forms a passagecompletely through the cylinder as well as the spongelike materialthrough which the tobacco composition may be inserted without rupturingor tearing the paper. As the tobacco composition is passed through thecylinder, the paper thereon absorbs the ammonium sulfamate solutioncontained in the sponge-like material. If conventional cigarettes areutilized, a passageway or bore in the cylinder and absorbent materialwill have a diameter on the order of of an inch. The speed at which thecigarette is passed through the bore or aperture depends upon theparticular concentration which is desired on the cigarette paper andalso the concentration of the solution in the sorbent material. Thecigarette can either be pushed manually through the device or in thealternative, can be pushed mechanically through the device at apredetermined speed as shown, e.g. U.S. Pat. 239,780. No matter how theammonium sulfamate is applied to the cigarette paper, the paper shouldnot be adversely afiected.

Inasmuch as water does not color the paper or otherwise adverselyafiFect the paper and also because water is inexpensive, an aqueoussolution of ammonium sulfamate is preferred. However, any other liquidin which ammonium sulfamate can be dispersed or dissolved, and whichdoes not adversely affect the smoking properties of the cigarette, canbe utilized.

In the exemplary embodiment the ammonium sulfamate is added to thecigarette paper while it is wrapped around the tobacco. In commercialproduction the ammonium sulfamate is added to the paper prior to beingwrapped around the tobacco. This can be done in the same way, and at thesame time, indeed in the same aqueous medium, as other solublecomponents are added to cigarette paper for controlling burningcharacteristics and color of the ash of cigarette paper.

To produce a cigarette containing between 0.3 and 0.5%, by weight, ofammonium sulfamate, a water solution containing between and 15% ofammonium sulfamate is prepared by dissolving the ammonium sulfamate inthe requisite amount of water. The aqueous solution thus prepared isthen added toa sorbent pad contained in the cylinder described supra andthe cigarette is passed therethrough. Depending upon the speed of thecigarette, between 0.3% and 0.5% of ammonium sulfamate is added to thecigarette.

A number of the cigarettes thus prepared were tested to determine theamount of sulfamate ion and the amount of ammonium ion in both thetobacco and the paper. As shown in the drawing, the amount of sulfarnateion in the paper is relatively constant whereas the ammonium ion in thepaper starts to migrate to the tobacco after about two weeks and, afterabout six weeks, there is between 70% to 80% of the ammonium ion in thetobacco.

As noted hereinabove, the smoke of a cigarette treated with ammoniumsulfamate in which the ammonium ion has not had time to migrate to thetobacco, does not have a reduction in components which cause biologicaldamage to mice and other test animals. This is demonstrated bycomprising the effect of smoke from untreated cigarettes, cigaretteswhich had ammonium sulfamate applied to them and were smoked after onlyten minutes, and cigarettes which had ammonium sulfamate applied to themand were smoked a month after treatment. All three types of cigaretteswere made from the same batch of a standard American blend of cigarettetobacco, and the same batch of cigarette paper, and were made on thesame machine. The only difference between the three types of cigaretteswas the ammonium sulfamate treatment. The untreated cigarettes provide acontrol against which to compare the treated cigarettes.

A 15% ammonium sulfamate solution was applied to to the paper of twogroups of cigarettes. Both types of cigarettes contain approximately 4to 6 mg. of the ammonium sulfamate per cigarette. One batch ofcigarettes was smoked ten minutes after the ammonium sulfamate wasapplied and the other batch of cigarettes was allowed to remain at 6'065F. and approximately 60% relative humidity for thirty days. Thecigarettes were smoked in a manifold-type smoking machine, onetwo-second puff per minute, with the suction pressure equal to thatwhich delivers a 17.5 ml./ sec. in sample cigarettes of the respectivegroups. The smoke was condened in two-liter collection flasks andimmersed in a dry ice-methanol mixlection flasks and immersed in a DryIce-methanol mixture. The condensate is removed from the flask withacetone. The acetone suspension is concentrated in a flash evaporatoruntil all the acetone is driven off. The remaining crude tar is treatedwith an equal volume of acetone and then eight volumes of heptane areadded slowly with vigorous shaking to provide a two phase system. Theupper phase is concentrated in a flash evaporator until all the heptaneis apparently driven off. It has been shown that this fraction of thetars contained all of the carcinogenic activity that is found in crudecigarette tar.

Female ICR Swiss mice at 60-70 days of age were used in the test forsebaceous gland suppression activity. The mice were divided into threegroups, each group having three to five mice. The mice is each groupwere shaded and painted with the cigarette tars two times daily forthree consecutive days. The animals were killed six days after therfirst application of test solution and the skins processed to stain thesebaceous glands in whole section and examined microscopically todetermine the extent of damage or complete destruction of the sebaceousgland. The criterion used was that any distant remnant of a gland whescored as a gland present. The results of such tests are shown in thefollowing Table I.

TABLE I Equiv. crude Av. percent tar. cone. glands No. of mice Group(gm/cc.) remaining tested A 2 43 14 B 2 30 9 C 3 65 10 The group labeledA were the untreated cigarettes, the group labeled B were the cigaretteswhich were smoked ten minutes after application of ammonium sulfamate,and the group labeled C were the cigarettes in which the ammoniumsulfamate was allowed to remain on the cigarette paper for a period ofabout a month, in which time the ammonium ion had migrated to thetobacco.

As is apparent from the foregoing table, the smoke of cigarettes inwhich the ammonium sulfamate has been allowed to remain on the paper foronly ten minutes has little or no effect in preventing destruction ofsebaceous glands in mice.

Similarly, the addition of ammonium sulfamate directly to the tobaccodoes not have as great an elfect in preventing tumors in mice as doesthe smoke from cigarettes wherein the ammonium sulfamate is added to thepaper and allowed to remain on the cigarette for a period of aboutthirty days. This is shown in the following tests wherein three types ofcigarettes were utilized. 7

All three types of cigarettes were made from the same batch of standardAmerican blend of cigarette tobacco and the same batch of cigarettepaper and were made on the same machine. The only difference between thethree types was the ammonium sulfamate treatment. Sample A consisted ofuntreated cigarettes. The cigarettes of sample B were prepared byspraying a 30% ammonium sulfamate solution on shredded, cured tobaccowhich is being rolled and tumbled. The amount of ammonium sulfamatesprayed on the tobacco was formed into cigarettes by wrapping thetobacco in cigarette paper. The cigarettes of sample C were prepared bydrawing them through a sponge soaked with a 15 aqueous solution ofammonium sulfamate. The amount of ammonium sulfamate on the cigarettepaper amounted to between 6 to 8 mg. per cigarette, which would be about.5%.75%. The cigarettes were allowed to stand at a temperature of 60-65F. at 60% relative humidity for from thirty to forty days. Thecigarettes were then smoked as set out above and the tars condensed fromsuch smoke as set out above. The tars were then applied to female ICRSwiss mice which were sixty to seventy days old. The mice were dividedinto three groups, in each group, and the mice in each group were shavedand painted two times daily, five days a week, for forty-one weeks witha solution of tar. About once a month the tar was replaced bya freshbatch which was obtained in exactly the same manner as the original tar.After a period of forty-one weeks, the mice which the tarsproduced fromthe group A cigarettes, had twenty-five tumors, the mice which weretreated with the tars produced from the group B cigarettes had seventeentumors, while the mice which were treated with the tars produced fromthe group C cigarettes had only nine tumors. Thus, the group B mice had32% fewer tumors than the group A mice while the group C mice had 64%fewer tumors. From the results of this test, the group C cigarettes aretwice as safe as the group B cigarettes.

In addition, tests indicate that smoke from cigarettes treated inaccordance with this invention did not atfect respiratory rate, minutevolume and total pulmonary resistance in guinea pigs, whereas smoke fromuntreated cigarettes do adversely affect the respiratory rate, minutevolumeand total pulmonary resistance of guinea pigs.

It will be understood that the foregoing description is onlyillustrative of the present invention and it is not intended that theinvention be limited thereto. Many other specific embodiments of thepresent invention will be apparent to one skilled in the art from theforegoing disclosure. All substitutions, alterations and modificationsof the present invention which come within the scope of the followingclaims or to which the present invention is readily susceptible withoutdeparting from the spirit and scope of this disclosure, are considered apart of the present invention.

I claim:

1. A method for significantly reducing the amount of components in smokeproduced from tobacco wrapped in paper which cause tumors on the skin ofmice and other biological damage, and significantly reducing thetoxicity of tar capable of being condensed from said smoke, as measuredby experiments on test animals, without significantly altering burningproperties of the tobacco and paper producing the smoke, or withoutaltering the appearance of the ash of said tobacco and paper, whichcomprises adding from about 0.1% to 1.0% by weight, based on thecombined weight of the paper and tobacco, of ammonium sulfamate to saidpaper and allowing said ammonium sulfamate to remain on said paper untilover 50% of the ammonium ion from said ammonium sulfaate has migrated tosaid tobacco.

2. A method according to claim 1 wherein the amount of ammoniumsulfamate added to the paper is from 0 .2% to 0.8% based on the combinedweight of the paper and tobacco.

References Cited UNITED STATES PATENTS 2,859,753 11/1958 Hitchcock eta1. 13115 FOREIGN PATENTS 702,919 2/ 1965 Canada.

OTHER REFERENCES Alford and Cardon: The Inhibition of Formation of3,4-Benzpyrene in Cigarette Smoke, from British Journal of Cancer, vol.10, 1956, pp. 498503.

MELVIN D. REIN, Primary Examiner US. Cl. X.R. l3 l--15

